RPC: Allow multiple RPC client programs to share the same transport Signed-off-by: Andreas Gruenbacher Acked-by: Olaf Kirch Signed-off-by: Trond Myklebust --- include/linux/sunrpc/clnt.h | 2 ++ net/sunrpc/clnt.c | 40 ++++++++++++++++++++++++++++++++++++++++ net/sunrpc/pmap_clnt.c | 3 +++ net/sunrpc/sunrpc_syms.c | 1 + 4 files changed, 46 insertions(+) Index: linux-2.6.12-rc1/include/linux/sunrpc/clnt.h =================================================================== --- linux-2.6.12-rc1.orig/include/linux/sunrpc/clnt.h +++ linux-2.6.12-rc1/include/linux/sunrpc/clnt.h @@ -114,6 +114,8 @@ struct rpc_clnt *rpc_create_client(struc struct rpc_clnt *rpc_new_client(struct rpc_xprt *xprt, char *servname, struct rpc_program *info, u32 version, rpc_authflavor_t authflavor); +struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *, + struct rpc_program *, int); struct rpc_clnt *rpc_clone_client(struct rpc_clnt *); int rpc_shutdown_client(struct rpc_clnt *); int rpc_destroy_client(struct rpc_clnt *); Index: linux-2.6.12-rc1/net/sunrpc/clnt.c =================================================================== --- linux-2.6.12-rc1.orig/net/sunrpc/clnt.c +++ linux-2.6.12-rc1/net/sunrpc/clnt.c @@ -241,6 +241,8 @@ rpc_clone_client(struct rpc_clnt *clnt) rpc_init_rtt(&new->cl_rtt_default, clnt->cl_xprt->timeout.to_initval); if (new->cl_auth) atomic_inc(&new->cl_auth->au_count); + new->cl_pmap = &new->cl_pmap_default; + rpc_init_wait_queue(&new->cl_pmap_default.pm_bindwait, "bindwait"); return new; out_no_clnt: printk(KERN_INFO "RPC: out of memory in %s\n", __FUNCTION__); @@ -329,6 +331,44 @@ rpc_release_client(struct rpc_clnt *clnt rpc_destroy_client(clnt); } +/** + * rpc_bind_new_program - bind a new RPC program to an existing client + * @old - old rpc_client + * @program - rpc program to set + * @vers - rpc program version + * + * Clones the rpc client and sets up a new RPC program. This is mainly + * of use for enabling different RPC programs to share the same transport. + * The Sun NFSv2/v3 ACL protocol can do this. + */ +struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *old, + struct rpc_program *program, + int vers) +{ + struct rpc_clnt *clnt; + struct rpc_version *version; + int err; + + BUG_ON(vers >= program->nrvers || !program->version[vers]); + version = program->version[vers]; + clnt = rpc_clone_client(old); + if (IS_ERR(clnt)) + goto out; + clnt->cl_procinfo = version->procs; + clnt->cl_maxproc = version->nrprocs; + clnt->cl_protname = program->name; + clnt->cl_prog = program->number; + clnt->cl_vers = version->number; + clnt->cl_stats = program->stats; + err = rpc_ping(clnt, RPC_TASK_SOFT|RPC_TASK_NOINTR); + if (err != 0) { + rpc_shutdown_client(clnt); + clnt = ERR_PTR(err); + } +out: + return clnt; +} + /* * Default callback for async RPC calls */ Index: linux-2.6.12-rc1/net/sunrpc/pmap_clnt.c =================================================================== --- linux-2.6.12-rc1.orig/net/sunrpc/pmap_clnt.c +++ linux-2.6.12-rc1/net/sunrpc/pmap_clnt.c @@ -53,6 +53,9 @@ rpc_getport(struct rpc_task *task, struc task->tk_pid, clnt->cl_server, map->pm_prog, map->pm_vers, map->pm_prot); + /* Autobind on cloned rpc clients is discouraged */ + BUG_ON(clnt->cl_parent != clnt); + spin_lock(&pmap_lock); if (map->pm_binding) { rpc_sleep_on(&map->pm_bindwait, task, NULL, NULL); Index: linux-2.6.12-rc1/net/sunrpc/sunrpc_syms.c =================================================================== --- linux-2.6.12-rc1.orig/net/sunrpc/sunrpc_syms.c +++ linux-2.6.12-rc1/net/sunrpc/sunrpc_syms.c @@ -42,6 +42,7 @@ EXPORT_SYMBOL(rpc_release_task); /* RPC client functions */ EXPORT_SYMBOL(rpc_create_client); EXPORT_SYMBOL(rpc_clone_client); +EXPORT_SYMBOL(rpc_bind_new_program); EXPORT_SYMBOL(rpc_destroy_client); EXPORT_SYMBOL(rpc_shutdown_client); EXPORT_SYMBOL(rpc_release_client);